Liquid adhesive compositions



United States Patent r 3,247,002 LIQUID ADHESIVE COMPOSITIONS Louislereny, Eric G. Gibbs, and Charles 0. Pyron, Dayton, (Ethic; Evelyn K.Pereny, enecutrix of said Louis 'Pereny, deceased; said Gibbs and saidPyron assignors to Protective Treatments, Inc, Dayton, Ohio, acorporation of Ohio No Drawing. Filed Apr. 15, 1963, Ser. No. 272,875Claims. (Cl. 106-477) This application is a continuation-in-part of ourearlier filed application, Serial No. 756,512, filed August 22, 1958,and now US Patent No. 3,090,694, and assigned to the saime assignee.

This invention relates to liquid adhesive compositions and, moreparticularly, to such compositions which may be applied in solution format the point and time of use and which will, even after solventevaporation, maintain a pressure sensitive adhesiveness of limitedtackiness for the repeated adhering and removal of an article at thearea or surface to which the adhesive was applied and without removal ofthe adhesive composition from the area or surface to which firstapplied.

According to this invention adhesive compositions are provided adaptedfor application in liquid solution form to a variety of surfaces to forman adhesive or tacky film thereon, which film, even after solventelimination therefrom, remains usefully tacky for a prolonged period,but such tackiness is maintainedat a relatively low level for therepeated adhering and removing of another article or surface. Theadvantages of adhesive compositions according to this invention areachieved generally by formulating the compositions with a plurality ofdistinct components for accomplishing the film forming, adhesionproducing, plasticizing, solvent evaporation, etc., properties orcharacteristics of the finished composition. These various componentsare proportioned, correlated, and combined to provide in the adhesivefilm not onlythe desired controlled, limited but prolonged tackiucss butalso to provide for having the cohesive or film tensile strength and theadhesiveness of the formulation as applied to the first surface to whichapplied from liquid form substantially exceed the pressure sensitivetackiness of the film after solvent removal so that, not only will theadhesive film preferentially adhere to the surface to which it is firstapplied, but also repeated removal of another surface applied to theadhesive film will neither disrupt the adhesive film nor removetherefrom adhesive clinging to the article or surface being removed.

As illustrative of applications or uses to which adhesive compositionsaccording to this invention are particularly adapted may be noted thesituation where the adhesive composition is applied in liquid form tothe skin of a patient about to undergo surgery and then a sterilesurgical drape of paper or plastic is positioned and adhered, andpossibly repositioned and readhered, to cover the skin of the patientand form a sterile field in the area to be operated on, as disclosed inPatent No. 3,060,932, issued October 30, 1962, and assigned to the sameassignee as this application; and other illustrative application may benoted as including resealable wrappers, containers, envelopes, and thelike.

One object of this invention is to provide liquid ashesive compositionsof the character described for application at the point and time of useto a surface to form thereover an adhesive film having a prolonged butlimited tackiness such that another article or surface may be adheredand readhered to the applied adhesive film without disruption thereof. 1

Another object of this invention is to provide adhesive compositions ofthe character described adapted to sprayable liquid application to asurface to provide thereover an adhesive film of prolonged tackiness andincluding distinct plasticizer, film forming, and adhesion producingcomponents formulated and proportioned [to give preferential adhesion ofthe adhesive film to the surface to which it is first applied in liquidform, cohesive or film tensile strength substantially and controllablysufficient to withstand disruption by removal of a pressure appliedmaterial, and a limited prolonged tackiness, all whereby another articleor surface, after having once been adhered by pressure to the adhesivefilm, may be removed there from cleanly and without either disruption ofthe adhesive film or carrying away on the article being removed part ofthe adhesive composition.

A further object of this invention is to provide a sterile liquidadhesive composition of the character described particularly adapted forthe sprayable application to human skin prior to a surgical operation sothat an area of prolonged tackiness is produced on the skin to receiveand hold a sterile drape or sheet, and including components soformulated and proportioned in the adhesive film to provide for firmadherence of the drape or sheet and yet to maintain the adhesive film onthe skin notwithstanding repeated adhering and removal of the drape orsheet cleanly from the skin without disruption of either the film on theskin or the drape or sheet, whether the latter be paper, fabric, orplastic.

Other object-s and advantages of this invention will be apparent fromthe following description and the ap pended claims.

The particular advantages and functioning of compositions embodying thisinvention can, perhaps, be conveniently considered with regard to therequirements and difiiculties and practicing of the surgical techniquedisclosed in said aforementioned copending application as illustrativeof one situation to which compositions embodying this invention areparticularly adapted. As there disclosed, it is desired to provide adisposable sterile sheeting or drape which can be adhesively attached tothe skin of a surgical patient to provide the surgeon with a largesterile field adjacent the point of the operation, with the adherence ofthe drape to the patient being continuous Without air bubbles, etc., andbeing such as to encapsulate or immobilize contaminating bacteria whichmay remain on the skin of the patient nothwithstanding antisepticpreoperative procedures. In the application of the drape or sheet, itmay have to be applied and removed and positioned and repositionedseveral time before a final satisfactory result is achieved with regardto smoothing it out, having it conform to the contours of the patientsbody, etc.

Since the drape or sheeting itself must be heat sterilized and since adrape or sheeting as large as, perhaps, four or five feet square may beutilized and applied without contamination in the sterile operatingroom, the difficulties inherent in attempeting to provide a pressuresensitive adhesive to the back of the sheet or drape itself areapparent. Similarly, an adhesive composition applied to the patients"skin at the point and time of use advantageously includescharacteristics of remaining tacky for at least the period necessary tocorrectly position and reposition the drape on the patient and,additionally, should have such correlation of cohesive and adhesivestrength as to be preferentially adhesive to the patients skin and notto strip off the patients skin with removal of the drape inrepositioning thereof, and yet have such pressure sensitive adhesivenessor tackiness for the drape material as to hold it firmly in place duringthe operation, but not be so adhesive therefor that there is danger oftearing the drape during removal thereof, whether the drape or sheetmaterial be paper, cloth, or plastic.

Conventionally, of course, pressure sensitive adhesives are applied in avariety of ways at the factory to a variety of backing materials forlater use in adhering the backing materials to another surfacee.g.,surgical adhesive tape, paper-backed masking tape, pressure sensitivelabels, cellophane tape, etc.but such adhesive materials and suchapplications are to be distinguished from the liquid application of anadhesive composition at the point of use for adhering to otherwisenonadhesive surfaces. Conventionally, also, various liquid adhesivecompositions designed for application at the point or time of use areintended to set up permanently upon evaporation of the solvent or otherdrying to form a permanent, nonreleasable and ultimately non-tackyadhesive bond between the two surfaces being adhered. Such a situation,also, is to be distinguished from the liquid application of an adhesivecomposition which, for a prolonged period, will remain usefully tackybut having a degree of tackiness or adhesiveness less than that whichwill form a permanent dry bond between the surfaces being adhered.

Even known pressure sensitive adhesives pre-applied to a backingmaterial are not conventionally formulated to provide the low degree oftack here advantageous, particularly when the drape or sheet materialhas no greater tensile strength or resistance to delamination thanpaper. For example, when a variety of known and commercially availablepressure sensitive and adhesive materials on a variety of backingmaterials were tested for the peel strength or adhesive strengthaccording to ASTM testing method D-903-49, and samples were prepared,coated and conditioned as therein described. The adhesives were coatedon smooth aluminum panels and a smooth sheet of polyvinyl chlorideplastic material adhered there- An Instron tensile testing device wasused to measure the force required to peel the smooth plastic sheet oneinch wide from the adhesive film being tested, at the separation rate ofsix inches per minute. Several commercially available surgical adhesivetapes measured in the vicinity of 350-410 grams, and pressure sensitivecommercial cellophane tapes registered about 310 grams, and theseparation occurred at the interface of the panel and the adhesive. Bycontrast, the adhesive composition embodying the invention tested at,not exceeding about 250 grams and preferred compositions at about 100grams by the same procedure, with separation occurring at the interfaceof the plastic sheet and the adhesive film. By comparison, thecompositions of this invention exhibit a tack value which is less thanthe chesive film strength and the adhesiveness thereof for the surfaceto which it is first applied.

In addition to a prolonged and limited tackiness, however, it is desiredthat compositions embodying this invention also have such tackiness oradhesive characteristics correlated with the film forming, cohesive orfilm tensile strength, and preferential adhesiveness for the surface towhich the composition is first applied, particularly, after eliminationof the solvent or vehicle in which original application of the liquidcompositions is achieved. The provision and predetermined control orcorrelation of these various characteristics, however, does notnecessarily inhere in the same materials which might provide thedesired, prolonged tackiness or limited tackiness and, in many cases,these several characteristics and properties may actually beinconsistent. Thus, for example, to one extent or another, certain filmforming materials also possess certain adhesive characteristics, andcertain'primarily adhesive materials also possess certain film fomingcharacteristics. If, however, a single component were utilized toprovide both the controlled cohesion or film strength characteristicsand the prolonged and limited tackiness desired, adjustment of thecohesion or film strength, as by plasticizing or otherwise, does notnecessarily result in concomitant adjustment or control of prolongedtackiness or limited tackiness.

Accordingly, adhesive compositions embodying this invention includedistinct components, which may be separately adjusted as to theirseveral characteristics and properties, for providing the desiredcohesion or strength or film forming properties and, additionally, thedesired control of adhesion producer or adhesive properties. As will beundestood, of course, the adhesiveness of the film forming component andwhatever film forming properties the adhesion producing component mayhave all combine to contribute to the final result in both these areasof the ultimate composition, and the control of the independentproperties of either of these components must be provided with dueregard to the others.

As will be understood, also, for any given film forming or adhesionproducing material, one direct and primary means for controlling thecohesion or film tensile strength or the adhesive tackiness or extent ofprolongation of tackiness after solvent removal includes the utilizationof a plasticizer component, either of the so-oalled polymeric type ofplasticizer or the ester-type of plasticizer. It has been found that theamount of plasticizer may be increased :in a particular composition offilm forming and adhesion producing materials to provide increasedprolongation of tackiness or a more limited tackiness or adhesivestrength, or adjustment of the peel strength as measured by the aboveASTM method. As plasticizer proportion is increased, the cohesiveness ortensile strength ofthe adhesive film, after solvent removal, isdiminished and substantially so that a point may ultimately be reachedwhere the cohesive film strength is so low, regardless of how low thepressure sensitive tackiness may be, that parts of the adhesive film,even after solvent removal, are disrupted or removed from the surface towhich the adhesive composition is first applied when an article or sheetor other surface is removed from the adhesive film after first beingbrought into pressure sensitive contact therewith.

Generally, considering the types of illustrative synthetic resin filmforming and adhesion producing materials noted herein, the cohesionand/or adhesive film strength are reduced below desired or satisfactorylimits when there is incorporated in the adhesive composition, as forthe purpose of prolonging or decreasing or otherwise adjusting thetackiness thereof, an amount of estertype plasticizer in excess of about200%, or an amount of polymeric-type plasticizer in excess of about 250%(by Weight) of the other film forming and adhesion producing componentsin the composition. Thus, the particular film forming and adhesionproducing components should be selected for compositions embodying thisinvention so that adhesion to the surface to which first applied, thedesired low degree of pressure sensitive tackiness and prolonged extentof tackiness of the applied film are achieved with amounts ofplasticizer less than the foregoing in order to produce a composition toform an adhesive film haying suflicient adhesion tothe surface to whichfirst applied and internal cohesion or film tensile strength towithstand being removed or torn or separated from the surface to whichit is applied in liquid form when another material or article or sheetis peeled away from the adhesive film after having been pressure-adheredthereto.

Additionally, as noted, it is preferred that the adhesive compositionsembodying this invention be prepared and adapted for liquid applicationin solutionv or emulsion form, and, most conveniently, for sprayapplication from, for example, aerosol spray-type containers.Particularly with such compositions prepared for. the surgicalapplication above noted, the constituents, including the solvent orvehicle, are chosen in addition to the desired adhesive and film formingproperties, to be relatively non-irritating to normal skin and with thesolvent chosen to provide the desired drying time as well as to benonsmarting and otherwise not unpleasant under the conditions of use.For example, with the specific compositions described below, theallergic reactivity level on human skin has been reported as being lessthan that of medically accepted commercial surgical adhesive tape, andthe solvents or vehicles utilized are selected to produce, when appliedto areas of normal human skin, a minimum of smarting or chilling orother medically or psychologically undesired effects. The originalcompositions before application are substantially stable andnon-oxidizing for convenient storage, and, preferably, maintaining theirown sterility as by including components which discourage the existenceof obnoxious bacteria.

Sprayable adhesive compositions having the attributes noted above havebeen produced according to this invention by the combination of a filmforming component, an adhesion producing component, a plasticizer, and abacteriostatic component, which components are admixed to form, with asuitable vehicle, a liquid solution or emulsion. Such compositions arestable to exposure to temperatures ranging from 6S F. to +165 F. instorage and are usable at temperatures ranging from F. up to 130 F. Whenvolatile organic solvents are used, the solvent evaporation. time can beeasily controlled, and is usually less than a half hour, after whichtime, as noted, the applied adhesive film still maintains its limitedtackiness for periods ranging up to many hours.

Such a composition is preferably packed in metal containers or so-calledaerosol spray-type containers accompanied by suitable well known spraypropellants such as halogenated-aliphatic type or compressed gaseoustype propellants. Such compositions may also be applied by brushing,flowing, Wiping on, or dipping.

The film forming component maybe of the class consisting of vinylpolymers (including vinyl chloride-vinylidine chloride copolymers, vinylchloride-vinyl acetate copolymers and carboxylated or hydroxylatedmodifications of such copolymers, vinyl chloride-butadiene polymers,vinyl butyral polymers, vinyl acetate polymers, etc.), polyacrylic andpolymethacrylic esters and polymers, cellulose acetate butyrate, ethylcellulose, and compatible combinations thereof. The adhesion producingcomponent may be one or compatible combinations of such resins aspolyacrylic or polymethacrylic esters and polymers, glycerol phthalate,abietic acid-glycerol and organic acid and/or phenol modifications ofsuch abietic acid glycerol, amine-aldehyde resins, and resins containingmaleic anhydride or phenols (including cresols). The plasticizer may beone or a combination of such monomeric substances as butyl phthallylbutyl glycollate, di- 2(ethyl-hexyl) azelate, acetylated castor oil,phthalic anhydnide-vegetable oil derivatives, tricresyl phosphate, 0.-and p.-toluene sulfonamidels; or polymeric substances such aschlorinated paraflin, cumarone-indene, sebacic acid polymers, treatedraw oticica and other vegetable oils (treated to produce compatibilitywith film formers).

The bacteriostatic agent (or, in some cases as noted below,bacteriocidal agent) may satisfactorily be maleic anhydride (asincluded, for example, in the adhesive component), phenols (includingcresols, chlorinated phenols and thio-chlorinated phenols, etc.). Thatis, especially with adhesive compositions for surgical uses, it isdesirable for the material to be sterile prior to use, as well asbacteriostatic. In some instances it may be convenient to include in thecomposition a bacteriocidal component of sufficient potency to killcontaminating bacteria which may be present in the containers for theadhesive composition and/or the processing and filling machinerytherefor. Particularly in cases Where the compositions embodying thisinvention are packaged in pressurized spray-type containers, the solventcomponent (such as the acetone and ethyl acetate solvents noted inExample I below) in combination with the Freon propellant in the sealedcontainer may be sufficiently bacteriocidal to render the compositionsas packaged sterile, and even without a special step of sterilizing thecontainers before or after packaging. In compositions not embodyingsolvents or other components which, with or without the propellant, maynot be considered of sufficient bacteriocidal potency for thissterilizing effect, additional bacteriocidal materials such aschloro-phenols, etc., may be added to the composition. Also, ininstances Where the compositions embodying this invention are packagedin other than sealed, pressurized,s-pray-type containers (e.g., openablecontainers for brush application) and/ or in other instances Where thepackaged compositions are repeatedly exposed to contamination of airborne batceria or contamination by a brush or other mechanicalapplicator, it may be desired to include in the compositions a morepotent bacteriocidal agent to provide a self-sterilizing compositionwhich will maintain its oWn surgical sterility despite repeatedcontaminations. Satisfactory results are achieved by adding, in such acase, to any of the formulations noted herein about 0.25 part by Weightof Actamer (a thio-chlorophenol) and/or 0.10 part Santophen I (achlorophenol).

It will be understood, of course, that one or another of the foregoingsynthetic resin components may be 0 eratively useful as, for example, anadhesion producer, although disclosed as a film former. That is, as iswell known among synthetic resin chemists, one particular type ofpolymer may be useful for one purpose When polymerized to a certaindegree, and yet the same basic synthetic resin structure, polymerized toa different degree, may be useful for a different purpose and/ or may 1e considered a different material within the context of the instantdisclosure. Similarly, a single resin component may simultaneouslyperform more than one of the desired film-forming, adhesion producing,plasticizing, etc., functions in a particular formulation.

Satisfactory volatile solvents for the above include one or acombination of such solvents as organic esters (e.g., ethyl acetate),ketones (e.g., acetone), organic ethers or oxides (e.g., ethyleneoxide), aromatic hydrocarbons (e.g., toluene), or chlorinated aliphatichydrocarbons (e.g., methylene chloride). The solvent component is chosento produce the desired drying rate and viscosity of liquid compositionwith regard to the method of application, case of storage, traumaticsmarting effect, etc. As noted above, such a solution may bepost-emulsified by the addition of appropriate emulsifying agents,anti-foaming agents, and water.

A satisfactory method of preparation of compositions using an organicsolvent includes adding the film former slowing to solvent withagitation in a suitable covered container taking care to avoidagglomeration. The remaining ingredients are added upon the completesolution of the film former and agitation is continued until allingredients are dissolved. After suitable filtration to remove anysuspended foreign matter, the liquid composition is packed into aerosolspray containers at approximately 0 F. in known manner, or otherwisepackaged as desired. Similarly, a satisfactory method of preparation ofwater-emulsion compositions embodying this invention includes dissolvingthe film-forming and adhesion producing components in the least amountof volatile solvents which will form a complete solution, adding anemulsifying agent (such as commercially available non-ionic, anionic, orcationic surface active agents) and, if desired, a conventionalanti-foaming agent or protective colloid with vigorous agitation untilwell dispersed, and then, also with agitation, adding sufiicient waterto produce the desired emulsion. It should also be noted thatemulsifiable film-forming and adhesion producing materials appropriatefor use in an emulsiontype composition embodying this invention arecommercially available already formed into water emulsions.

Specific illustrative examples of compositions embodying this invention,with which satisfactory results have been achieved, are:

Example 1 Parts by weight Vinyl chloride-vinyl acetate resin (VAGH) 8Maleic anhydride modified glycerol-abietic-acid resin (Amberlac D-96) 3Epoxidated-oil type plasticizer (Paraplex G-50) 4 Butyl phthalyl-butylglycollate plasticizer (Santicizer B-l6) 4 Ethyl acetate 36 Acetone 40Methyl isobutyl ketone Example 2 Hard film type polyester resin ofacrylic and methacrylic acid (Acryloid B-82, 40% solids) 12 Softer filmvariation of same resin (Acryloid C1()- LV, 40% solids) 18 Butyl benzylphthalate plasticizer (Santicizer 160) 9 Methyl ethyl ketone 61 Example3 Vinyl chloride copolymer with vinylidiene chloride (Geon 222) 15Diphenyl octyl phosphate plasticizer (Santicizer 141) 5 Methyl ethylketone 80 Example 4 Soft film type N-butyl methacrylate resin polymer(Lucite 44) 15 Decyl butyl phthalate plasticizer 8 Methyl ethyl ketone77 Example 5 Soft film type N-butyl methacrylate resin polymer Lucite44) 15 Rosin derived alkyd type resin adhesive (Neolyn 23) 4Di-iso-octyl phthalate plasticizer (Hercofiex 200) 4 Methyl ethyl ketone77 Example 6 Hard film forming cellulose ethyl ether (Dow ethylcellulose N-lO) Z-biphenyl-diphenyl phosphate resin (Dow 5) 12Isopropanol (99%) 20 Toluene 40 Butyl acetate 18 xample 7 Water emulsionof soft film forming type polyacrylic resin (Rhoplex FRN, 40% solids) 45Water emulsion of medium hard film type polyacrylic resin (RhoplexB-6OA, 46% solids) Water 40 Example 8 8 Example 9 Parts by weightAcrylic ester polymer (Acrylic 13-37) 12 Low molecular weight, slightlytacky acrylic ester polymer (Acryloid C-lO-LV) Solvent (Methyl ethylketone) Example 10 Acrylic ester polymer (Acryloid B-72) l6 Plasticizer(Paraplex G-50 epoxidated oil type) 4 Methyl ethyl ketone 80 Example 11Polyvinyl acetate and alkyl maleate (Gelva "IS-70,

55% water emulsion) 60 Butyl benzyl phthalate plasticizer (Santicizer 6Water 34 Example 12 Acrylic polymer (Rhoplex 13-5, 46% solids, in wateremulsion) 30 Acrylic polymer, medium hard film type (Rhoplex 60A, 46%solids in water emulsion) 20 Water 50 In the foregoing examples, itshould be noted that all the parts given are by weight. Also, forcompleteness, the various components are described in terms of themanufacturers descriptions, as well as the manufacturers gradedesignations. For example, the Acryloid resins are manufacturedcommercially by Rohm & Haas as are the various Rhoplex and Amberlacresins and Paraplex plasticizers. The Santicizer plasticizers are theproduct of Monsanto Chemical Company, the Geon resins are produced by B.F. Goodrich Chemical Company, the Lucite by duPont, the Neolyn resinsand Hercofiex plasticizers by Hercules Powder Company, and the Dowproducts by Dow Chemical Company.

The variations in materials and proportions in the foregoing examplesare meant to illustrate how the various materials of different degreesof inherent adhesiveness and pressure sensitive tackiness and differentdegrees of film strength or film hardness may be admixed and combined toprovide the desired characteristics of an adhesive material according tothis invention. Thus, in the first example, different components areillustrated for providing the primary film forming and adhesionproducing characteristics, with a blend of different plasticizers forachieving-the desired end result. Also the solvents are particularlychosen for the various substances involved with, for example, theinclusion of a solvent such as acetone for its fast drying andsterilizing effect and a solvent such as methyl isobutyl ketone tocontrol and somewhat delay complete solvent evaporation. Example 2 isparticularly illustrative of the utilization of two essentially similarresins but polymerized to different degrees coordinated to produce thedesired fim forming cohesion characteristics and more or lessindependent adhesion and tackiness producing characteristics. Example 4illustrates a formulation in which one polymer material is such as toadmit of the desired control of tackiness with desired film strengthmerely by appropriate selection and proportions of plasticizer, whileExample 5 is similar to Example 4 but of a somewhat greater degree oftack by the inclusion of an additional adhesion producing alkyd resin,and Examples 7 and 8 illustrate water emulsion type formulations, ascompared to organic solvent types.

Examples 9 and 10 illustrate a composition similar to that of Example 4,while Example 11 is similar to the composition of Example 4 except thesolvent is water and the composition is in the form of an emulsion.Example 12 is similar to the emulsions of Examples 7 and 8 utilizinghowever polymers of different molecular weights.

While the compositions and products herein described constitutepreferred embodiments of the invention, it is to Q be understood thatthe invention is not limited to these precise compositions and products,and that changes may be made therein without departing from the scope ofthe invention which is defined in the appended claims.

What is claimed is:

1. A liquid adhesive composition for liquid application to a surface asan adherent film thereon with limited but prolonged pressure sensitivetackiness for another surface brought into contact therewith, consistingessentially of an organic film forming and adhesion producing polymerselected from the group consisting of vinyl polymers and copolymers,polyacrylic esters and polymers, polymethacrylic esters and polymers,cellulose acetate butyrate, ethyl cellulose, glycerol phthalate resins,abietic acid-glycerol resins and organic acid and phenol modificationsthereof, amine-aldehyde resins, maleic anhydride, polyphenyl esterresins, phenol resins and alkyl resins, a liquid vehicle for saidorganic polymer selected from the group consisting of volatile organicsolvents and water, and a plasticizer selected from the group consistingof polymeric and ester type plasticizers, said plasticizer being presentin an amount from about 15% to about 65% based on the weight of saidorganic polymer to provide after evaporation of the liquid vehicle afilm adherent to the surface to which it is applied, the exposed surfaceof said film having a pressure sensitive tackiness sufficient to adherethereto a smooth vinyl plastic sheet and not exceeding approximately 250grams measured as peel strength by the ASTM testing method D-903-49herein disclosed, in which one test surface is a smooth plastic sheet ofthe vinyl type and the other surface is a smooth aluminum sheet, andsaid tackiness of said exposed surface of said film for said plasticsheet being less than each of the cohesive strength of said film and theadhesiveness thereof to said surface to which it is applied.

2. A liquid adhesive composition for liquid application to human skin toform thereover a continuous adherent film having preferentialadhesiveness to said skin and cohesive film strength to maintain saidfilm continuous thereover and having limited but prolonged pressuresensitive tackiness for a vinyl type plastic sheet brought into contactwith said film consisting essentially of a liquid vehicle selected fromthe group consisting of volatile organic solvents and water andbeing'present in an amount of between 50 and 80 parts by Weight, a filmforming component of high cohesive film strength but adhesive strengthinadequate for producing said preferential adhesiveness to said skin andpresent in an amount of between 10 and 45 partsby weight, said filmforming component being selected from the group consisting of vinylpolymers and copolymers, polyacrylic esters and polymers,polymethacrylic esters and polymers, cellulose acetate butyrate, ethylcellulose, glycerol phthalate resins, abietic acid-glycerol resins andorganic acid and phenol modifications thereof, amine-aldehyde resins,maleic anhydride, polyphenyl ester resins, phenol resins and alkydresins, a polymeric component having adequate plasticizing effectivenessbut an adhesive strength inadequate for producing said pressuresensitive tackiness and adhesiveness selected from the group consistingof polymeric type and ester type plasticizers and being present in anamount of between and 15 parts by weight, one of said componentsplasticizing the other to provide after evaporation of the liquidvehicle an adherent film having preferential adhesion to skin andcohesive film strength sufiicient to maintain said film continuousthereover while providing an exposed surface having a lower limit ofpressure sensitive tackiness sufi'icient to adhere thereto a smoothvinyl sheet, and an upper limit of said tackiness not exceedingapproximately 250 grams measured as peel strength by the ASTM testingmethod D-903-49 herein disclosed, in which one test surface is a smoothplastic sheet of the vinyl type and the other surface is a smoothaluminum sheet, and said tackiness of said exposed film surface for saidplastic sheet being less than each of the cohesive ll) strength of saidfilm and the adhesiveness thereof to human skin.

3. A liquid adhesive composition for liquid application to human skin toform thereover a continuous adherent film having preferentialadhesiveness to said skin and cohesive film strength to maintain saidfilm continuous thereover and having limited but prolonged pressuresensitive tackiness for a smooth sheet of vinyl plastic brought intocontact with said film consisting essentially of a volatile liquidvehicle selected from the group consisting of volatile organic solventsand water, a film forming component of high cohesive film strength andadhesive strength inadequate for producing said preferentialadhesiveness to said skin selected from the group consisting of vinylpolymers and copolymers, polyacrylic esters and polymers,polymethacrylic esters and polymers, cellulose acetate butyrate, ethylcellulose, glycerol phthalate resins, abietic acid-glycerol resins andorganic acid and phenol modifications thereof, amine-aldehyde resins,maleic anhydride resins, polyphenyl esters, phenol resins and alkydresins,

a polymeric component having adequate plasticizing effectiveness but anadhesive strength inadequate for producing said pressure sensitivetackiness and adhesiveness selected from the group consisting ofpolymeric type and ester type plasticizers and present in an amount upto 250% and 200% by Weight, respectively, based on the weight of saidfilm forming component to provide after evaporation of said liquidvehicle an adherent film, said film having preferential adhesion to skinand cohesive film strength sufiicient to maintain said film continuousthereover while providing an exposed surface having a lower limit ofpressure sensitive tackiness sufiicient to adhere thereto a smooth vinylsheet, and an upper limit of said tackiness not exceeding approximately250 grams measured as peel strength by the ASTM testing method D-903-49herein disclosed, in which one test surface is a smooth plastic sheet ofthe vinyl type and the other surface is a smooth aluminum sheet, saidcomponents and said liquid vehicle being non-toxic and non-irritating tohuman skin, and said tackiness of said exposed film surface for saidplastic sheet being less than each of the cohesive strength of said filmand the adhesiveness thereof to human skin.

4. A liquid adhesive composition for application to skin as an adherentfilm thereon having an exposed tacky surface with limited but prolongedpressure sensitive tackiness for a smooth vinyl plastic sheet broughtinto contact therewith consisting essentially of 40 to parts by weightof a liquid vehicle selected from the group consisting of volatileorganic solvents and water, a film forming and adhesive producingcomponent present in an amount between about 10 to 60 parts by weightselected from the group consisting of vinyl polymers and copolymers,polyacrylic esters and polymers, polymethacrylic esters and polymers,cellulose acetate butyrate, ethyl cellulose, glycerol phthalate resin,abietic acid-glycerol resins and organic acid and phenol modificationsthereof, amine-aldehyde resins, maleic anhydride resins, polyphenylesters, phenol resins and alkyd resins, a plasticizer present in saidfilm forming and adhesive producing component in an amount sufficient toprovide an adherent film after evaporation of the liquid vehicle, saidplasticizer being selected from the group consisting of butylphthallyl-butyl glycolate, di-2(ethyl-'hexyl)azelate, epoxidated oil,acetylated castor oil, phthalic anhydride vegetable oil derivatives,tricresyl phosphate, toluene sulfonamides, butyl benzyl phthalate,diphneyl actyl phosphate, decyl butyl phthalate, dioctyl phthalate,chlorinated paraffin, cumarone-indene, sebacic acid polymers, acrylicand methyacrylic acid polymers, compatible raw oiticica, and compatiblecombinations thereof, and the exposed surface of said film having apressure sensitive tackiness sufficient to adhere thereto to a smoothvinyl plastic sheet and not exceeding approximately 250 grams measuredas peel strength by the ASTM testing method D90349 herein disclosed, inwhich one test surface is a smooth plastic sheet of the vinyl type andthe other surface is a smooth aluminum sheet, and said tackiness of saidexposed surface of said film for said plastic sheet being less than eachof the cohesive strength of said film and the adhesiveness thereof toskin. 7

5. A liquid adhesive composition as set forth in claim 4 in which saidplasticizer is present in an amount about 4 and 9 parts by weight.

1 2. References Cited by the Examiner UNITED STATES PATENTS 3,090,6945/1963 Pereny et a1 106177 5 ALEXANDER H. BRODMERKEL, Primary Examiner.

ALFRED L. LEAVITT, Examiner.

1. A LIQUID ADHESIVE COMPOSITION FOR LIQUID APPLICATION TO A SURFACE ASAN ADHERENT FILM THEREON WITH LIMITED BUT PROLONGED PRESSURE SENSITIVETACKINESS FOR ANOTHER SURFACE BROUGHT INTO CONTACT THEREWITH, CONSISTINGESSENTIALLY OF AN ORGANIC FILM FORMING AND ADHESION PRODUCING POLYMERSELECTED FROM THE GROUP CONSISTING OF VINYL POLYMERS AND COPOLYMERS,POLYACRYLIC ESTERS AND POLYMERS, POLYMETHACRYLIC ESTERS AND POLYMERS,CELLULOSE ACETATE BUTYRATE, ETHYL CELLULOSE, GLYCEROL PHTHALATE RESINS,ABIETIC ACID-GLYCEROL RESINS ORGANIC ACID AND PHENOL MODIFICATIONSTHEREOF, AMINE-ALDEHYDE RESINS, MALEIC ANHYDRIDE, POLYPHENYL ESTERRESINS, PHENOL RESINS AND ALKYL RESINS, A LIQUID VEHICLE FOR SAIDORGANIC POLYMER SELECTED FROM THE GROUP CONSISTING OF VOLATILE ORGANICSOLVENTS AND WATER, AND A PLASTICIZER SELECTED FROM THE GROUP CONSISTINGOF POLYMERIC AND ESTER TYPE PLASTICIZERS, PLASTICIZER BEING PRESENT INAN AMOUNT FROM ABOUT 15% TO ABOUT 65% BASED ON THE WEIGHT OF SAIDORGANIC POLYMER TO PROVIDE AFTER EVAPORATE OF THE LIQUID VEHICLE A FILMADHERENT TO THE SURFACE TO WHICH IT IS APPLIED, THE EXPOSED SURFACE OFSAID FILM HAVING A PRESSURE SENSITIVE TACKINESS SUFFICIENT TO ADHERETHERETO A SMOOTH VINYL PLASTIC PLASTIC SHEET AND NOT EXCEEDINGAPPROXIMATELY 250 GRAMS MEASURED AS PEEL STRENGTH BY THE ASTM TESTINGMETHOD D-903-49 HEREIN DISCLOSED, IN WHICH ONE TEST SURFACE IS A SMOOTHPLASTIC SHEET OF THE VINYL TYPE AND THE OTHER SUFACE IS A SMOOTHALUMINUM SHEET, AND SAID TACKINESS OF SAID EXPOSED SURFACE OF SAID FILMOF SAID PLASTIC SHEET BEING LESS THAN EACH OF THE COHESIVE STRENGTH OFSAID FILM AND THE ADHESIVENESS THEREOF TO SAID SURFACE TO WHICH IT ISAPPLIED.